http://mirror.bg.host.ag/ubuntu/
http://ubuntu.ipacct.com/ubuntu/
https://mirror.telepoint.bg/ubuntu/
http://mirrors.daticum.com/ubuntu/archive/
http://mirrors.neterra.net/ubuntu/
https://mirrors.storpool.com/ubuntu/archive/
http://ubuntu.uni-sofia.bg/ubuntu/
http://archive.ubuntu.com/ubuntu/